API standard 650 cylindrical liquid-storage tank gauge float wells

Weld inspection of API standard 650 cylindrical liquid-storage tank, vertical oil tank wall plate: In the welding inspection process of oil tank wall plate, attention should be paid to the defects of thick wall plate, such as incomplete penetration, incomplete root fusion and cracks. If there is a root incomplete penetration defect, it is necessary to open the weld joint with carbon arc air gouging and grinding machine grinding, or even weld through, and then weld again after the defect is removed.

Except as permitted by API standard 620 Q.8.6, the test shall be conducted after the entire tank is complete, before the insulation is applied. Except as limited by foundation or stress conditions, the test shall consist of filling the tank with water to the design liquid level and applying an overload air pressure of 1.25 times the pressure for which the vapor space is designed. The load on the supporting foundation shall preferably not exceed the established allowable bearing value for the tank site. Where a thorough evaluation of the foundation justifies a temporary increase, the established allowable bearing may be increased for the test condition, but the increase shall be not more than 25%.

Selection of nominal diameter D of API 650 storage tank. In the design calculation of API 650 storage tank, the bottom plate thickness is the net plate thickness, that is, the actual thickness minus the corrosion allowance. In the design and calculation of API standard 650 cylindrical liquid-storage tank wall thickness in hydrostatic test, the thickness of bottom plate is the total thickness of steel plate.